U.S. patent application number 14/411389 was filed with the patent office on 2015-05-21 for biodegradable blood vessel occlusion and narrowing.
The applicant listed for this patent is V.V.T. Med Ltd.. Invention is credited to Zeev Brandeis.
Application Number | 20150142025 14/411389 |
Document ID | / |
Family ID | 49998820 |
Filed Date | 2015-05-21 |
United States Patent
Application |
20150142025 |
Kind Code |
A1 |
Brandeis; Zeev |
May 21, 2015 |
BIODEGRADABLE BLOOD VESSEL OCCLUSION AND NARROWING
Abstract
A biodegradable blood vessel narrowing device, comprising: a
biodegradable element; an anchoring element; wherein said anchoring
element is anchored to a blood vessel wall and at least one
external dimension of said biodegradable element is reduced upon
biodegradation of said biodegradable element thereby pulling said
blood vessel walls toward one another.
Inventors: |
Brandeis; Zeev; (Rosh
HaAyin, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
V.V.T. Med Ltd. |
Kfar-Saba |
|
IL |
|
|
Family ID: |
49998820 |
Appl. No.: |
14/411389 |
Filed: |
June 25, 2013 |
PCT Filed: |
June 25, 2013 |
PCT NO: |
PCT/IL2013/050538 |
371 Date: |
December 25, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61664222 |
Jun 26, 2012 |
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61722826 |
Nov 6, 2012 |
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Current U.S.
Class: |
606/151 |
Current CPC
Class: |
A61F 2002/016 20130101;
A61B 2017/00004 20130101; A61F 2/01 20130101; A61B 17/1214
20130101; A61B 17/12172 20130101; A61B 2017/2215 20130101; A61B
17/12109 20130101; A61B 2017/00867 20130101; A61B 17/064 20130101;
A61B 2017/1205 20130101; A61B 17/00491 20130101; A61B 17/12131
20130101; A61B 17/12036 20130101; A61B 17/1204 20130101; A61B
2017/0641 20130101 |
Class at
Publication: |
606/151 |
International
Class: |
A61B 17/12 20060101
A61B017/12; A61B 17/00 20060101 A61B017/00 |
Claims
1. A biodegradable blood vessel narrowing device, comprising: a
biodegradable element; an anchoring element sized and shaped to be
anchored to a blood vessel wall when located in a blood vessel
lumen; and at least one external dimension of said biodegradable
element is reduced upon biodegradation of said biodegradable
element thereby pulling said blood vessel walls toward one
another.
2. The device of claim 1, wherein said device occludes a blood
vessel upon said device deployment in said blood vessel.
3. The device of claim 1, wherein said device partially occludes a
blood vessel upon said device deployment in said blood vessel.
4. The device of claim 1, wherein said anchoring element is made of
a shape memory alloy (SMA).
5. The device of claim 1, wherein said anchoring element is made of
a biocompatible polymer.
6. The device of claim 1, wherein a degradation of said
biodegradable element is initiated by external degradation
means.
7. The device of claim 1, wherein said anchoring element comprises
a plurality of anchoring legs, each said anchoring leg having at
least one anchoring tooth for anchoring to a blood vessel wall and
a distance between at least two of respective said anchoring teeth
shortens upon biodegradation of said biodegradable element.
8. The device of claim 7, wherein said plurality of anchoring legs
essentially encircles said biodegradable element.
9. The device of claim 7, further comprising a constriction element
wherein said constriction element and upon biodegradation of said
biodegradable element said constriction element applies pressure on
said plurality of anchoring legs thereby bringing said plurality of
anchoring legs to a closer proximity to one another.
10. The device of claim 7, further comprising a constriction
element wherein said constriction element encircles said plurality
of anchoring legs and said biodegradable element is positioned
essentially inside said constriction element and upon
biodegradation of said biodegradable element said constriction
element applies pressure on said plurality of anchoring legs
thereby pulling said plurality of anchoring legs.
11. The device of claim 7, wherein said biodegradable element being
positioned between at least one of said anchoring legs and a part
of said device which is adjacent to at least one of said anchoring
legs and upon degradation of said biodegradable element the
distance between said at least one of said anchoring legs and said
part.
12. The device of claim 7, wherein said anchoring leg has a first
leg part and a second leg part carrying said at least one anchoring
tooth, said biodegradable element being positioned between said
first leg part and said second leg part and upon degradation of
said biodegradable element the distance between said first part and
said second part shortens.
13. The device of claim 7, wherein said biodegradable element
encircles said plurality of anchoring legs thereby fastening said
plurality of anchoring legs and a distance between said plurality
of anchoring legs after degradation of said biodegradable element
is shorter than a distance between said plurality of anchoring legs
prior to degradation of said biodegradable element.
14. The device of claim 7, wherein each of said plurality of
anchoring legs further comprise a retention element and said
plurality of anchoring legs have a twisted state in which said
plurality of anchoring legs are twisted around one another and an
untwisted state and a distance between said plurality of anchoring
legs in said twisted state is bigger than a distance between said
plurality of anchoring legs in said untwisted state and said
biodegradable element encircles said plurality of anchoring legs in
their twisted state thereby fastening said plurality of anchoring
legs and said retention element restricts the movement of said
biodegradable element and upon degradation of said biodegradable
element said plurality of anchoring legs switch from a said twisted
state to said an untwisted state.
15. The device of claim 7, wherein each of said plurality of
anchoring legs is a spring shaped element.
16. The device of claim 1, further comprising an internal chamber
wherein said device is capsule shaped and filling of said internal
chamber enlarges an external dimension of said device to fit a
blood vessel.
17. The device of claim 1, wherein said biodegradable blood vessel
narrowing device has an outer surface and said anchoring element
comprises: a glue chamber internal to said capsule; a plurality of
glue channels connecting said chamber to said capsule surface; and
a bio-compatible glue; wherein said biocompatible glue flows from
said glue chamber to said outer surface through said plurality of
glue channels thereby gluing said biodegradable blood vessel
narrowing device to a vessel wall.
18. The device of claim 17, further comprising a layer and said
layer is positioned external to said glue chamber and internal to
biodegradable element and upon degradation of said biodegradable
element said layer applies pressure on said glue chamber thereby
inserting said bio-compatible glue into said plurality of glue
channels.
19. The device of claim 1, further comprising: a chamber internal
to said biodegradable blood vessel narrowing device; and a channel
connecting said chamber to a surface of said capsule; wherein said
channel transfers a bio-absorbable material between said chamber
and an exterior of said capsule.
20. The device of claim 1, further comprising an occlusion element,
wherein said occlusion element occludes a blood vessel.
21. A method for occluding and narrowing a blood vessel,
comprising: deploying a biodegradable blood vessel narrowing device
in a blood vessel; and attaching an anchoring element of said
biodegradable blood vessel narrowing device to walls of said blood
vessel; wherein narrowing of said blood vessel is mechanically
linked to biodegradation of said biodegradable blood vessel
narrowing device.
22. The method of claim 21, further comprising applying external
degradation means to said device for initiating biodegradation.
23. The method of claim 21, further comprising filling a chamber in
said device with a bio-absorbable material.
24. The method of claim 21, wherein said attachment of an anchoring
element is performed by releasing bio-compatible glue from said
biodegradable blood vessel narrowing device and gluing of said
biodegradable blood vessel narrowing device to a blood vessel
wall.
25. The method of claim 21, further comprising filling a glue
chamber in said biodegradable blood vessel narrowing device with
bio-compatible glue.
Description
FIELD AND BACKGROUND OF THE INVENTION
[0001] The present invention, in some embodiments thereof, relates
to blood vessel treatment and, more particularly, but not
exclusively, to biodegradable devices and/or methods for blood
vessel occlusion and narrowing.
[0002] A malfunction in the ability of veins or arteries to supply
or remove blood is associated with medical conditions such as
varicose vein expansion, aneurisms, tumors, trauma and dissection
of blood vessels.
[0003] Varicose veins appear in 20-25% of women and 10-15% of men.
Most varicose veins are considered a cosmetic condition rather than
a medical condition; however, in some cases, hindered circulation
may cause pain, disfiguring, swelling, discomfort, a tingling
sensation, itching and/or a feeling of heaviness.
[0004] Several techniques and procedures to treat varicose veins
exist. Vein stripping involves tying off of the upper end of a vein
and then removing the vein. Vein stripping is typically performed
in an operating room under general anesthesia. Approximately
150,000 vein stripping surgeries are performed each year in the
U.S. Vein stripping associated risks include risks linked to
general anesthesia such as anesthesia allergies, infections etc. In
addition, tissue around the stripped vein may become bruised and
scarred causing a feeling of "tightness" in the leg. Damaged may
cause numbness and paralysis of part of the leg.
[0005] Endovenous laser treatment is typically performed done
in-office under local anesthesia. Endovenous laser treatment uses
intense heat to remove a vein, which may lead to an increased risk
of developing blood clots. Treated veins can also become irritated
and inflamed, leading to pain and swelling in the legs. The treated
area can begin to tingle or become burned from the heat.
[0006] Radiofrequency occlusion is typically performed done
in-office under local anesthesia or in an ambulatory surgery
setting. A small tube or catheter is used and threaded along the
vein using ultrasound guidance. Local anesthetic is injected along
the way to help ensure the patient's comfort throughout the
procedure. Once the vein is canalized, sound waves are applied to
heat and collapse the vein from the top, down. The vein will
eventually result in a thin scar tissue and is absorbed by the
body's natural processes. Following treatment with radiofrequency
occlusion, a compression bandage is applied to the leg to aid in
the healing process. This should be kept in place for a couple of
days and then compression stockings are worn for another two to
three weeks to continue to aid the healing process. Patients may
walk shortly after treatment and most are able to resume normal
activities or return to work after a few days provided they avoid
heavy lifting and wear their compression stockings. There may be a
chance of bleeding, infection or blood clots with radiofrequency
occlusion as with many other procedures. A unique complication that
is associated with radiofrequency occlusion, however, is skin burn
due to the method of occlusion used during treatment.
[0007] Ultrasound-guided sclerotherapy is typically performed done
in-office under local anesthesia. Side effects that are applicable
for standard sclerotherapy are also applicable to ultrasound-guided
sclerotherapy, although the magnitude of certain complications,
when they occur, may be greater. Standard sclerotherapy side
effects include skin ulceration or necrosis, deep vein thrombosis,
allergic reaction, arterial injection, pulmonary embolus, nerve
injury, wound breakdown and wound inflammation.
[0008] The artificial blocking of blood flow is known generically
as "embolization" and/or "occlusion". The embolization of a vessel
in an organ may be used to treat a variety of maladies; typically
though, embolization is used.
SUMMARY OF THE INVENTION
[0009] According to an aspect of some embodiments of the present
invention there is provided a biodegradable blood vessel narrowing
device, comprising: a biodegradable element; an anchoring element
sized and shaped to be anchored to a blood vessel wall when located
in a blood vessel lumen; and at least one external dimension of the
biodegradable element is reduced upon biodegradation of the
biodegradable element thereby pulling the blood vessel walls toward
one another. Optionally, the device occludes a blood vessel upon
the device deployment in the blood vessel. Optionally, the device
partially occludes a blood vessel upon the device deployment in the
blood vessel. Optionally, the anchoring element is made of a shape
memory alloy (SMA). Optionally, the anchoring element is made of a
biocompatible polymer. Optionally, a degradation of the
biodegradable element is initiated by external degradation means.
Optionally, the anchoring element comprises a plurality of
anchoring legs, each the anchoring leg having at least one
anchoring tooth for anchoring to a blood vessel wall and a distance
between at least two of respective the anchoring teeth shortens
upon biodegradation of the biodegradable element. Optionally, the
plurality of anchoring legs essentially encircles the biodegradable
element. Optionally, the device further comprises a constriction
element wherein the constriction element and upon biodegradation of
the biodegradable element the constriction element applies pressure
on the plurality of anchoring legs thereby bringing the plurality
of anchoring legs to a closer proximity to one another. Optionally,
the device further comprises a constriction element wherein the
constriction element encircles the plurality of anchoring legs and
the biodegradable element is positioned essentially inside the
constriction element and upon biodegradation of the biodegradable
element the constriction element applies pressure on the plurality
of anchoring legs thereby pulling the plurality of anchoring legs.
Optionally, the biodegradable element being positioned between at
least one of the anchoring legs and a part of the device which is
adjacent to at least one of the anchoring legs and upon degradation
of the biodegradable element the distance between the at least one
of the anchoring legs and the part. Optionally, the anchoring leg
has a first leg part and a second leg part carrying the at least
one anchoring tooth, the biodegradable element being positioned
between the first leg part and the second leg part and upon
degradation of the biodegradable element the distance between the
first part and the second part shortens. Optionally, the
biodegradable element encircles the plurality of anchoring legs
thereby fastening the plurality of anchoring legs and a distance
between the plurality of anchoring legs after degradation of the
biodegradable element is shorter than a distance between the
plurality of anchoring legs prior to degradation of the
biodegradable element. Optionally, each of the plurality of
anchoring legs further comprise a retention element and the
plurality of anchoring legs have a twisted state in which the
plurality of anchoring legs are twisted around one another and an
untwisted state and a distance between the plurality of anchoring
legs in the twisted state is bigger than a distance between the
plurality of anchoring legs in the untwisted state and the
biodegradable element encircles the plurality of anchoring legs in
their twisted state thereby fastening the plurality of anchoring
legs and the retention element restricts the movement of the
biodegradable element and upon degradation of the biodegradable
element the plurality of anchoring legs switch from a the twisted
state to the untwisted state. Optionally, each of the plurality of
anchoring legs is a spring shaped element. Optionally, the device
further comprises an internal chamber wherein the device is capsule
shaped and filling of the internal chamber enlarges an external
dimension of the device to fit a blood vessel. Optionally, the
biodegradable blood vessel narrowing device has an outer surface
and the anchoring element comprises: a glue chamber internal to the
capsule; a plurality of glue channels connecting the chamber to the
capsule surface; and a bio-compatible glue; wherein the
biocompatible glue flows from the glue chamber to the outer surface
through the plurality of glue channels thereby gluing the
biodegradable blood vessel narrowing device to a vessel wall.
Optionally, the device further comprises a layer and the layer is
positioned external to the glue chamber and internal to
biodegradable element and upon degradation of the biodegradable
element the layer applies pressure on the glue chamber thereby
inserting the bio-compatible glue into the plurality of glue
channels. Optionally, the device further comprises: a chamber
internal to the biodegradable blood vessel narrowing device; a
channel connecting the chamber to a surface of the capsule; wherein
the channel transfers a bio-absorbable material between the chamber
and an exterior of the capsule. Optionally, the device further
comprises an occlusion element, wherein the occlusion element
occludes a blood vessel.
[0010] According to an aspect of some embodiments of the present
invention there is provided a method for occluding and narrowing a
blood vessel, comprising: deploying a biodegradable blood vessel
narrowing device in a blood vessel; and attaching an anchoring
element of the biodegradable blood vessel narrowing device to walls
of the blood vessel; wherein narrowing of the blood vessel is
mechanically linked to biodegradation of the biodegradable blood
vessel narrowing device. Optionally, the method of further
comprises applying external degradation means to the device for
initiating biodegradation. Optionally, the method further comprises
filling a chamber in the device with a bio-absorbable material.
Optionally, the attachment of an anchoring element is performed by
releasing bio-compatible glue from the biodegradable blood vessel
narrowing device and gluing of the biodegradable blood vessel
narrowing device to a blood vessel wall. Optionally, the method
further comprises filling a glue chamber in the biodegradable blood
vessel narrowing device with bio-compatible glue.
[0011] Unless otherwise defined, all technical and/or scientific
terms used herein have the same meaning as commonly understood by
one of ordinary skill in the art to which the invention pertains.
Although methods and materials similar or equivalent to those
described herein can be used in the practice or testing of
embodiments of the invention, exemplary methods and/or materials
are described below. In case of conflict, the patent specification,
including definitions, will control. In addition, the materials,
methods, and examples are illustrative only and are not intended to
be necessarily limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Some embodiments of the invention are herein described, by
way of example only, with reference to the accompanying drawings.
With specific reference now to the drawings in detail, it is
stressed that the particulars shown are by way of example and for
purposes of illustrative discussion of embodiments of the
invention. In this regard, the description taken with the drawings
makes apparent to those skilled in the art how embodiments of the
invention may be practiced.
[0013] In the drawings:
[0014] FIG. 1A is an illustration of a biodegradable blood vessel
narrowing device with multiple anchoring legs in a twisted state,
according to some embodiments of the present invention;
[0015] FIG. 1B is an illustration of a biodegradable blood vessel
narrowing device with multiple anchoring legs in an untwisted
state, according to some embodiments of the present invention;
[0016] FIG. 1C is an illustration of a biodegradable blood vessel
narrowing device with multiple anchoring legs in an open state,
according to some embodiments of the present invention;
[0017] FIG. 1D is an illustration of a biodegradable blood vessel
narrowing device with multiple anchoring legs in a closed state,
according to some embodiments of the present invention;
[0018] FIG. 2A is an illustration of a biodegradable blood vessel
narrowing device with multiple anchoring legs having a
biodegradable element between their first and second parts in a
pre-degradation state, according to some embodiments of the present
invention;
[0019] FIG. 2B is an illustration of a biodegradable blood vessel
narrowing device with multiple anchoring legs having a
biodegradable element between their first and second parts in a
degraded state, according to some embodiments of the present
invention;
[0020] FIG. 2C is an illustration of a biodegradable blood vessel
narrowing device with an encircling constriction element with an
internal biodegradable element in an open state, according to some
embodiments of the present invention;
[0021] FIG. 2D is an illustration of a biodegradable blood vessel
narrowing device with an encircling constriction element with an
internal biodegradable element in a closed state, according to some
embodiments of the present invention;
[0022] FIG. 3A is an illustration of a biodegradable blood vessel
narrowing device with spring shaped anchoring legs spaced by a
biodegradable element in a pre-degradation state, according to some
embodiments of the present invention;
[0023] FIG. 3B is an illustration of a biodegradable blood vessel
narrowing device with spring shaped anchoring legs spaced by a
biodegradable element in a degraded state, according to some
embodiments of the present invention;
[0024] FIG. 4A is an illustration of a biodegradable blood vessel
narrowing device with an occlusion element in a pre-degradation
state, according to some embodiments of the present invention;
[0025] FIG. 4B is an illustration of a biodegradable blood vessel
narrowing device with an occlusion element in a degraded state,
according to some embodiments of the present invention;
[0026] FIG. 5A is an illustration of a biodegradable blood vessel
narrowing device with a glue chamber in a pre-degradation state,
according to some embodiments of the present invention;
[0027] FIG. 5B is an illustration of a biodegradable blood vessel
narrowing device with a glue chamber in a degraded state, according
to some embodiments of the present invention;
[0028] FIG. 6A is an illustration of a biodegradable blood vessel
narrowing device with an empty internal chamber and a channel in a
pre-degradation state, according to some embodiments of the present
invention;
[0029] FIG. 6B is an illustration of a biodegradable blood vessel
narrowing device with a filled internal chamber and a channel in a
pre-degradation state, according to some embodiments of the present
invention;
[0030] FIG. 6C is an illustration of a biodegradable blood vessel
narrowing device with a filled internal chamber and a channel in a
degraded state, according to some embodiments of the present
invention;
[0031] FIG. 7 is a flowchart of a method 700 for narrowing a blood
vessel, according to some embodiments of the present invention;
and
[0032] FIG. 8 is an illustration of a blood clot cage, according to
some embodiments of the present invention.
DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0033] The present invention, in some embodiments thereof, relates
to devices and methods for blood vessel occlusion and narrowing
and, more particularly, but not exclusively, to biodegradable blood
vessel narrowing devices and methods for occluding and narrowing a
blood vessel using a biodegradable element.
[0034] According to some embodiments of the present invention,
there are provided a biodegradable blood vessel narrowing devices
which anchor to a blood vessel wall and narrow the blood vessel
upon a degradation of its biodegradable element. Such a
biodegradable blood vessel narrowing device has a biodegradable
scaffold or block, referred to herein as a biodegradable element
and one or more anchoring elements for anchoring the biodegradable
blood vessel narrowing device to the blood wall. For brevity, the
one or more anchoring elements are referred to herein as an
anchoring element. The anchoring element includes one or more
anchoring legs, hooks and/or biocompatible glue. The anchoring
element may be made of a shape memory alloy (SMA). Upon degradation
of the biodegradable element the blood vessel the anchoring element
changes its formation to pull the blood vessel walls inwardly,
thereby narrowing the blood vessel. The anchored biodegradable
blood vessel narrowing device is set to occlude the blood vessel
completely and/or partially, immediately and/or overtime. Occlusion
may be performed by an occlusion element that attaches to the blood
vessel independently of the biodegradable blood vessel narrowing
device and/or is attached to the biodegradable blood vessel
narrowing device.
[0035] Variations of the blood vessel narrowing device achieve the
blood vessel narrowing with different configurations. The device
may have anchoring legs, be capsule shaped, tube shaped and/or have
anchoring springs. The biodegradable elements shape, number,
position and/or relation with the anchoring element may differ
between these variations. For example, the biodegradable element
may include one or more biodegradable ring encircling anchoring
legs. The anchoring legs are twisted around one another and are
held in that state by the biodegradable ring. A retention element
secures the ring in place and prevents and/or limits its movement.
Upon degradation of the biodegradable ring the anchoring legs
switch from twisted open state to an untwisted closed state. The
legs are closer to each other in the untwisted closed state. With
their movement towards one another the anchoring legs pull with
them the blood vessel wall and narrow the blood vessel.
[0036] A blood vessel narrowing device is inserted into a blood
vessel in a state that fits the blood vessel shape and dimensions.
The blood vessel narrowing device is then deployed in the blood
vessel. The anchoring element attaches to the blood vessel walls.
The attachment may be performed using biocompatible glue. When a
bio-absorbable material is used it is first inserted into an
internal chamber of the device. The insertion of the bio-absorbable
material may bring the anchoring element into a position that
allows its attachment to the blood vessel walls. Then the insertion
means, for example a capillary, may be removed.
[0037] Before explaining at least one embodiment of the invention
in detail, it is to be understood that the invention is not
necessarily limited in its application to the details of
construction and the arrangement of the components and/or methods
set forth in the following description and/or illustrated in the
drawings and/or the Examples. The invention is capable of other
embodiments or of being practiced or carried out in various
ways.
[0038] Before explaining at least one embodiment of the invention
in detail, it is to be understood that the invention is not
necessarily limited in its application to the details set forth in
the following description or exemplified by the Examples. The
invention is capable of other embodiments or of being practiced or
carried out in various ways.
[0039] Referring now to the drawings, FIGS. 1-6 illustrate
variations of a biodegradable blood vessel narrowing device 105,
205, 305, 405, 605. FIGS. 1A, 2A, 3A, 4A, 5A, and 6A illustrate a
pre-degradation state with the biodegradable element 110 and/or the
constriction element 130 not yet degraded. FIGS. 1B, 2B, 3B, 4B, 5B
and 6C illustrate a degraded state with the biodegradable element
110 and/or the constriction element 130 partially and/or fully
degraded.
[0040] FIGS. 1A and 1B illustrate a biodegradable blood vessel
narrowing device 105 with multiple anchoring legs 120 in a twisted
state 101A and untwisted state 101B, according to some embodiments
of the present invention. The biodegradable blood vessel narrowing
device 105 has multiple anchoring legs 120. In these examples four
anchoring legs 120 are depicted. The anchoring legs 120 have sharp
teeth 122 used for anchoring the device 105 to a blood vessel wall.
Optionally, the anchoring legs 120 are made of an SMA such as
copper-aluminium-nickel, nickel-titanium, zinc alloy, copper alloy,
gold alloy and/or iron alloy. When the anchoring legs 120 are
twisted, as in FIG. 1A, they are spread apart to touch opposing
sides of a blood vessel wall. The twisted state 101A is maintained
by a biodegradable constriction element 130. In this example the
biodegradable constriction element is a loop which encircles the
anchoring legs 120. Such a constriction element 130 is held in its
position by one or more retention elements 135 on one or more of
the anchoring legs 120, for example segments of the anchoring legs
120. Here, the retention element 135 is shaped as an arch. The
constriction element 130 is made of a biodegradable material. As
used herein, biodegradable material means a biodegradable,
bio-absorbable and/or re-absorbable material for internal use, of a
synthetic and/or natural source which can be degraded (i.e., broken
down) and/or absorbed in a physiological environment such as by
proteases. Biodegradability may depend on the availability of
degradation substrates (i.e., biological materials or portion
thereof which are part of the polymer), the presence of
biodegrading materials (e.g., microorganisms, enzymes, proteins)
and the availability of oxygen, carbon dioxide and/or other
nutrients (for aerobic organisms, microorganisms and/or portions
thereof). Examples of biodegradable material include, but are not
limited to: a polyglycolic acid (PGA), Maxon--PGA, Tri-Methylene
Carbonate (TMC), Vicryl PGA, Vicryl Polylactide, polylactic acid
(PLA), polyglycolic acid (PLGA), Dexon olyglycolide,
polycaprolactone (PCL), polydioxanone (PDO), Polydioxanone (PDS),
polyethyleneglycol (PEG), PEG-DMA, Polyethylenimine (PEI),
hyaluronic acid, catgut suture material, gelatin, cellulose,
nitrocellulose, collagen, gelatin, albumin, fibrin, alginate,
hydrogels, chitosan copolymers and/or other synthetic and
naturally-occurring biodegradable materials and/or mixtures
thereof. The biodegradable material may be a homo-polymer or a
copolymer. When the biodegradable material of the constriction
element degrades, the constriction element 135 is loosened and the
anchoring legs 120 transfer from the twisted state 101A, as
depicted in FIG. 1A, to the untwisted state 101B as depicted in
FIG. 1B. Optionally, the change from the twisted state 101A to the
untwisted state 101B is promoted by the shape memory of SMA
anchoring legs 120: The SMA anchoring legs 120 tend to be
essentially straight and close to one another as a result of their
shape memory. Without external pressure and/or retention the SMA
anchoring legs 120 tend to move to the untwisted state 101B. The
anchoring legs 120 are closer to one another in the untwisted state
101B than in the twisted state 101A. Optionally the biodegradable
blood vessel narrowing device 105 may have a blood clot cage 890 as
illustrated in FIG. 8. The biodegradation may be gradual. Gradual
biodegradation may achieve a gradual narrowing of a blood vessel.
The biodegradable blood vessel narrowing device 105 may occlude the
blood vessel immediately and completely upon insertion and/or
deployment. Optionally, the biodegradable blood vessel narrowing
device 105 in a twisted state 101A partially occludes the blood
vessel upon insertion and/or deployment. Then, upon gradual
transition to an untwisted state 101B the biodegradable blood
vessel narrowing device 105 achieves a higher level of occlusion.
Optionally, upon an essentially complete biodegradation of the
constriction element 130, an essentially complete occlusion of the
blood vessel is achieved by the biodegradable blood vessel
narrowing device 105. Optionally, an accompanying occlusion device
is used to achieve immediate occlusion and the biodegradable blood
vessel narrowing device 105 narrows the blood vessel over time.
Optionally, the accompanying occlusion device is removed when
occlusion is achieved by the biodegradable blood vessel narrowing
device 105.
[0041] FIGS. 1C and 1D illustrate a biodegradable blood vessel
narrowing device 105 with multiple anchoring legs 120 in an open
state 101C and a closed state 101D, according to some embodiments
of the present invention. The biodegradable blood vessel narrowing
device 105 illustrated in FIGS. 1C and 1D is a variation of the
biodegradable blood vessel narrowing device 105 depicted in FIGS.
1A and 1B respectively. One aspect of this correspondence is that
the anchoring legs 120 are spread apart in the open state 101C and
in the twisted state 101A. In these states 101A, 101C the anchoring
legs 120 can touch opposing sides of a blood vessel wall. In this
example the anchoring legs 120 are spread apart by a biodegradable
element 110. The anchoring legs 120 encircle the biodegradable
element 110. Optionally, no retention element is required to hold
the biodegradable element 110 between the anchoring legs 110.
Optionally, the biodegradable element 110 contains one or more non
degradable parts and/or a hollow chamber. The tendency of the
anchoring legs to be in a closed configuration 101D may apply
physical pressure towards the biodegradable element 110. In this
example the biodegradable element 110 is shaped as a tube.
[0042] FIGS. 2A and 2B illustrate a biodegradable blood vessel
narrowing device 205 with multiple anchoring legs 220 having a
biodegradable element between their first 224 and second parts 226,
according to some embodiments of the present invention. FIG. 2A
illustrates an open state 201A of the anchoring legs 220. The
biodegradable blood vessel narrowing device 105 illustrated in
FIGS. 2A and 2B is a variation of the biodegradable blood vessel
narrowing device 105 depicted in FIGS. 1A, 1C and 1B, 1D
respectively. The biodegradable blood vessel narrowing device 105
illustrated in FIG. 1C has four anchoring legs 220. Each leg has a
first part 224 and a second part 226. The second part 226 of the
anchoring leg 220 carries an anchoring tooth 222. The anchoring
teeth 222 anchor to the walls of a blood vessel. Optionally,
anchoring of the anchoring teeth 222 to blood vessel walls is
performed without penetrating a blood vessel wall. A biodegradable
element 210 is located between the first part 224 and the second
part 226 of the anchoring legs 220 in an open state 201A. Upon the
degradation of the biodegradable element 210, the biodegradable
element 210 external dimensions become smaller and the first 224
and second 226 parts of the anchoring legs 220 get closer to one
another. The walls of a blood vessel are pulled towards one another
upon the degradation of the biodegradable element 210 as a result
of the distance shortening between the first 224 and second 226
parts of the anchoring legs 220. Optionally, the change in the
biodegradable element's 210 external dimensions is promoted by the
shape memory of anchoring legs 120 made of SMA.
[0043] FIGS. 2C and 2D illustrate a biodegradable blood vessel
narrowing device 205 with an encircling constriction element 230
with an internal biodegradable element 210 in an open state 201C
and in a closed state 201D, according to some embodiments of the
present invention. In the open state 201C the anchoring legs 220
are further apart from one another compared to the closed state
201D. The biodegradable blood vessel narrowing device 105
illustrated in FIGS. 2C and 2D is a variation of the biodegradable
blood vessel narrowing device 105 depicted in FIGS. 1A, 1C, 2A and
1B, 1D, 2D respectively. In this example, the constriction element
230 encircles the anchoring legs 220. Optionally, the constriction
element 230 encircles some of the anchoring legs 220. Optionally,
the biodegradable blood vessel narrowing device 205 has multiple
constriction elements 230. Each of the constriction elements 230
encircles a group of anchoring legs 220. Optionally, multiple
constriction elements 230 may encircle the same anchoring legs 220,
thereby creating an overlap between the groups of encircled
anchoring legs 220. There is a biodegradable element 210 inside the
constriction element 230. Optionally, the biodegradable element 210
is completely internal to the constriction element 230, having
essentially no part of the biodegradable element 210 exposed to the
blood. Optionally, the constriction element 230 is made of a non
permeable material which does not enable the degraded parts of the
biodegradable element 210 to pass from the internal side 231 of the
constriction element 230 to its external side 232 which is exposed
to the blood. Optionally, the biodegradable element 210 is located
in the center of the constriction element 230. Optionally, the
biodegradable element 210 is positioned symmetrically in respect to
the shape of the constriction element 230 in order to promote
symmetric narrowing of blood vessel walls. Optionally, the
biodegradable blood vessel narrowing device 205 is removed the
blood vessel after the blood vessel is narrowed. Optionally, drugs
affecting the blood vessel diameter are provided prior to, along
with and/or after inserting and/or deploying the biodegradable
blood vessel narrowing device 205.
[0044] FIGS. 3A and 3B illustrate a biodegradable blood vessel
narrowing device 305 with spring shaped anchoring legs 320A, 320B,
according to some embodiments of the present invention. In this
example there are two anchoring legs 320A, 320B, each shaped as a
spring. Each of the spring shaped anchoring legs 320A, 320B has
anchoring teeth 322. The anchoring teeth 322 anchor the
biodegradable blood vessel narrowing device 305 to a blood vessel
wall 340. A biodegradable element 310 spreads the spring shaped
anchoring legs 320A, 320B apart to create an open state 301A. The
spring shaped anchoring legs 320A, 320B tend to contract and wrap
back together in a closed state 301B. The spring shaped anchoring
legs 320A, 320B apply pressure on the biodegradable element 310.
Upon degradation of the biodegradable element 310 the spring shaped
anchoring legs 320A, 320B move towards one another creating a
closed state 301B. In the closed state 301B the distance between
the spring shaped anchoring legs 320A, 320B is reduced. The
movement of the spring shaped anchoring legs 320A, 320B pulls the
blood vessel walls toward each other which in turn narrow the blood
vessel. Optionally, the spring shaped anchoring legs 320A, 320B is
made of a shape memory alloy SMA comprising:
copper-aluminium-nickel, nickel-titanium, zinc alloy, copper alloy,
gold alloy and/or iron alloy. Optionally, a retention element
maintains the position of the biodegradable element 310 with
respect to the spring shaped anchoring legs 320A, 320B. Optionally,
the biodegradable blood vessel narrowing device 305 has more than
two anchoring legs 320A, 320B. Optionally, the plurality of spring
shaped anchoring legs is organized in groups of anchoring legs.
[0045] FIGS. 4A and 4B illustrate a biodegradable blood vessel
narrowing device 405 with an occlusion element 450, according to
some embodiments of the present invention. The biodegradable blood
vessel narrowing device 405 illustrated in FIGS. 4A and 4B is a
variation over the biodegradable blood vessel narrowing device 105
depicted in FIGS. 1A, 1C and 1B, 1D respectively. In this example,
there are no anchoring legs. The biodegradable element 410 carries
an anchoring element such as anchoring teeth 422. When the
biodegradable element 410 degrades the blood vessel walls are
pulled therealong, narrowing the blood vessel. Optionally, the
occlusion element 450 is attached to the biodegradable blood vessel
narrowing device 405. Optionally, the attached occlusion element is
anchored to the blood vessel walls along with the biodegradable
blood vessel narrowing device 405. Optionally, the occlusion
element 450 has a second anchoring element, such as anchoring teeth
452. Optionally, the biodegradable blood vessel narrowing device
405 occludes a blood vessel even without the occlusion element 450,
and the occlusion element 450 supplies an additional safety net for
complete and/or immediate occlusion of a blood vessel. The
biodegradable blood vessel narrowing device 405 narrows the blood
vessel walls 340, 540, 640, 840 to fit the device's 405 own
dimensions, thereby occluding the blood vessel.
[0046] FIGS. 5A and 5B illustrate a biodegradable blood vessel
narrowing device 505 with a glue chamber, according to some
embodiments of the present invention. The biodegradable blood
vessel narrowing device 505 has a glue chamber 560 and a
biodegradable element 510. The glue chamber 560 may be internal to
the biodegradable element 510 as illustrated. Glue channels 565
connect the glue chamber 560 with the outer surface 570 of the
biodegradable blood vessel narrowing device 505. The biocompatible
glue passes through the glue channels 565. The bio-compatible glue
reaches the outer surface 570 of the biodegradable blood vessel
narrowing device 505. The bio-compatible glue glues the device 505
to a blood vessel wall after the device 505 deployment in a blood
vessel. The biodegradable blood vessel narrowing device 505 is
depicted here in two states: with a glue chamber 560 full of
biocompatible glue and a biodegradable element 510 as illustrated
in FIG. 5A and with a glue chamber 560 essentially empty of
biocompatible glue and a degraded biodegradable element 510 as
illustrated in FIG. 5B. Optionally, the biodegradable blood vessel
narrowing device 505 is capsule shaped. Optionally, the
biodegradable blood vessel narrowing device 505 has multiple glue
chambers 560. Multiple glue chambers 560 may enable to reduce the
distance between the glue chamber 560 and the outer surface 570,
thereby reducing the force needed to inject the bio-compatible glue
through the glue channels 565 and/or the distance and/or time the
glue has to pass before sticking to a blood vessel wall 540. These
may reduce the chances of a glue channel 565 block occurrence.
Optionally, the biocompatible glue is released by applying external
pressure onto the device 505.
[0047] Optionally, the biocompatible glue is released by injecting
a second material into the glue chamber 560. The increase in fluid
pressure forces the biocompatible into the glue channels 565. The
second material, which is optionally inserted into the glue chamber
560, may be a fast bio-absorbable such as water, the patient's own
blood etc. Optionally, the glue is released as a result of the
pressure applied by the blood vessel walls on the biodegradable
blood vessel narrowing device 505. Optionally, the glue release is
dependent on degradation of the biodegradable element 510 and/or on
absorption of a bio-absorbable material. Optionally, a layer 575 is
external to the biodegradable element 510. The additional layer 575
may be made of a biocompatible polymer, a biocompatible material
and/or an SMA. Upon degradation of the biodegradable element 510,
the biodegradable element 510 essentially collapses towards the
glue chamber. As a result the biocompatible polymer 575 shrinks and
creates pressure towards the glue chamber, thereby releasing the
bio-compatible glue. The biocompatible polymer layer 575 may be
partial or essentially completely cover the biodegradable element
510. Optionally, a bio-absorbable element may function in a similar
to the biodegradable element with respect to the bio-compatible
glue release. Using a bio-absorbable element instead, in
combination with and/or in addition to a biodegradable element 510
may reduce the glue release time. Optionally, the glue is not
present in the glue chamber 560 at the time of device 505
deployment. The biocompatible glue may be inserted into the glue
chamber 560 once the device 505 is in a blood vessel in a similar
manner to that illustrated in FIG. 6. The glue may be inserted to
the device 505 through the glue channels and/or through a different
opening.
[0048] FIGS. 6A, 6B and 6C illustrate a biodegradable blood vessel
narrowing device 605 with an internal chamber 468 and a channel
685, according to some embodiments of the present invention. When
the biodegradable blood vessel narrowing device 605 is deployed in
a blood vessel the internal chamber 668 is typically empty. Once
the device 605 is deployed a biocompatible material is inserted
through the channel 685. The channel 685 connects the internal
chamber 668 with the surface 670 of the device 605. The channel may
penetrate the degradable element 610. Optionally, another layer 675
of material may essentially encircle the biocompatible element 610.
This layer may also be made of a biodegradable material, an SMA
and/or a biocompatible polymer. The additional later 675 may apply
pressure on internal layers promoting their degradation, shape
modification and/or insertion into channel, as illustrated in FIG.
5 by the additional layer 575. Optionally, the degradable element
610 has a hollow tube which fits channel 685. Optionally, the
channel 685 extends beyond the surface 670 of the device.
Optionally, the channel 685 is inserted after deployment. The
biocompatible material may be a bio-absorbable material such as
water and/or other biocompatible absorbable materials and/or a
biodegradable material such as collagen and/or biodegradable
materials as listed above in FIGS. 1A and 1B. The operator inserts
biocompatible material into the internal chamber 468 until the
surface of the device 605 anchors to the blood vessel walls 640.
Optionally, the device 605 contains an occlusion agent for
occluding the blood vessel. The occlusion may be complete and/or
partial, i.e. some of the blood streaming through the blood vessel
is blocked and some of the blood still flows through the blood
vessel with the partially occluding device 605. Optionally, more
biocompatible material is inserted to create pressure on the blood
vessel walls. Optionally, monitoring means such as a camera and/or
a pressure detector are used to determine when to stop the
biocompatible material insertion. Optionally, once the
biocompatible material is contained in the internal chamber 668 the
channel 685 is removed. When the biocompatible material and/or the
biodegradable element 610 the blood vessel walls which are anchored
to the device 610 are pulled inward, thereby narrowing the blood
vessel. Optionally, the biocompatible material in the internal
chamber 668 is absorbed and/or degraded in a different pace
compared to the degradation pace of the biodegradable element
610.
[0049] Reference is now also made to FIG. 7 which is a flowchart of
a method 700 for narrowing a blood vessel, according to some
embodiments of the present invention. First, a biodegradable blood
vessel narrowing device is deployed in a blood vessel 705.
Optionally, the blood vessel is occluded 707. The occlusion may be
performed by the biodegradable blood vessel narrowing device 105,
205, 305, 405, 505 and/or 605. Optionally, the occlusion is
performed by an independent occlusion device. Optionally, the
deployed biodegradable blood vessel narrowing device is one of the
variations illustrated in FIGS. 1A-6C and/or a combination thereof.
Then, optionally, glue chamber is filled in the biodegradable blood
vessel narrowing device is filled with bio-compatible glue 710.
Then, an anchoring element of said biodegradable blood vessel
narrowing device is attached to the blood vessel walls 715. The
attachment may be performed by hooks, by biocompatible glue and/or
other anchoring means. The anchoring element may attach to the
blood vessel wall by itself upon deployment. For example, hooks on
anchoring legs that are in close proximity to a blood vessel walls.
Optionally, the device 105, 205, 305, 405, 505 and/or 605 is moved
in the blood vessel to facilitate the attachment of the anchoring
element to the blood vessel walls. Optionally, external means are
applied to facilitate the attachment of the anchoring element to
the blood vessel walls such as applying pressure on tissue around
blood vessel. Optionally, a chamber in the biodegradable blood
vessel narrowing device is filled with a bio-absorbable material.
The filling of a chamber in the biodegradable blood vessel
narrowing device with a bio-absorbable may be performed as
illustrated in FIG. 6B. The bio-absorbable material fill may
promote the anchoring of the device to the blood vessel walls by
bringing the blood vessel walls and the anchoring means closer
together. Then, optionally, external degradation means are applied
to the biodegradable blood vessel narrowing device for initiating
biodegradation 720. External degradation means may be selected
from: external pressure, light emission, sound waves, degradation
promoting agent, chemical compound delivery and/or a laser beam.
Optionally, a chamber in said device is filled with a
bio-absorbable material.
[0050] Reference is now also made to FIG. 8 which illustrates a
blood clot cage 890, according to some embodiments of the present
invention. The blood clot cage is depicted here deployed in a blood
vessel 840. The blood vessel 840 has a front 840A and a rear side
840B as defined by the blood flow which occurs from the rear side
840B to the front side 840A. The blood clot cage 890 may be
positioned in front of the biodegradable narrowing device. The
blood clot cage 890 assists in catching a blood clot that may be
formed as a result of the blood vessel occlusion.
[0051] It is expected that during the life of a patent maturing
from this application many relevant SMA, biocompatible glues,
bio-absorbable materials, biocompatible polymers, external
degradation means, anchoring means will be developed and the scope
of the terms SMA, biocompatible glue, bio-absorbable material,
biocompatible polymer, external degradation mean, and/or anchoring
mean are intended to include all such new technologies a
priori.
[0052] As used herein the term "about" refers to .+-.10%.
[0053] The terms "comprises", "comprising", "includes",
"including", "having" and their conjugates mean "including but not
limited to". This term encompasses the terms "consisting of" and
"consisting essentially of".
[0054] The phrase "consisting essentially of" means that the
composition or method may include additional ingredients and/or
steps, but only if the additional ingredients and/or steps do not
materially alter the basic and novel characteristics of the claimed
composition or method.
[0055] As used herein, the singular form "a", "an" and "the"
include plural references unless the context clearly dictates
otherwise. For example, the term "a compound" or "at least one
compound" may include a plurality of compounds, including mixtures
thereof.
[0056] The word "exemplary" is used herein to mean "serving as an
example, instance or illustration". Any embodiment described as
"exemplary" is not necessarily to be construed as preferred or
advantageous over other embodiments and/or to exclude the
incorporation of features from other embodiments.
[0057] The word "optionally" is used herein to mean "is provided in
some embodiments and not provided in other embodiments". Any
particular embodiment of the invention may include a plurality of
"optional" features unless such features conflict.
[0058] Throughout this application, various embodiments of this
invention may be presented in a range format. It should be
understood that the description in range format is merely for
convenience and brevity and should not be construed as an
inflexible limitation on the scope of the invention. Accordingly,
the description of a range should be considered to have
specifically disclosed all the possible subranges as well as
individual numerical values within that range. For example,
description of a range such as from 1 to 6 should be considered to
have specifically disclosed subranges such as from 1 to 3, from 1
to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as
well as individual numbers within that range, for example, 1, 2, 3,
4, 5, and 6. This applies regardless of the breadth of the
range.
[0059] Whenever a numerical range is indicated herein, it is meant
to include any cited numeral (fractional or integral) within the
indicated range. The phrases "ranging/ranges between" a first
indicate number and a second indicate number and "ranging/ranges
from" a first indicate number "to" a second indicate number are
used herein interchangeably and are meant to include the first and
second indicated numbers and all the fractional and integral
numerals therebetween.
[0060] It is appreciated that certain features of the invention,
which are, for clarity, described in the context of separate
embodiments, may also be provided in combination in a single
embodiment. Conversely, various features of the invention, which
are, for brevity, described in the context of a single embodiment,
may also be provided separately or in any suitable subcombination
or as suitable in any other described embodiment of the invention.
Certain features described in the context of various embodiments
are not to be considered essential features of those embodiments,
unless the embodiment is inoperative without those elements.
[0061] Although the invention has been described in conjunction
with specific embodiments thereof, it is evident that many
alternatives, modifications and variations will be apparent to
those skilled in the art. Accordingly, it is intended to embrace
all such alternatives, modifications and variations that fall
within the spirit and broad scope of the appended claims.
[0062] All publications, patents and patent applications mentioned
in this specification are herein incorporated in their entirety by
reference into the specification, to the same extent as if each
individual publication, patent or patent application was
specifically and individually indicated to be incorporated herein
by reference. In addition, citation or identification of any
reference in this application shall not be construed as an
admission that such reference is available as prior art to the
present invention. To the extent that section headings are used,
they should not be construed as necessarily limiting.
* * * * *